arXiv:cond-mat/0111455 · Physical Review Letters

Transverse Breathing Mode of an Elongated Bose-Einstein Condensate

Frédéric Chevy, Vincent Bretin, P. Rosenbusch, Kirk W. Madison, Jean Dalibard

Published Jun 6, 2002• 173 citations

Abstract

We study experimentally the transverse monopole mode of an elongated rubidium condensate. Because of the scaling invariance of the nonlinear Schr\"odinger (Gross-Pitaevskii) equation, the oscillation is monochromatic and sinusoidal at short times, even under strong excitation. For ultralow temperatures, the quality factor $Q\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}{\ensuremath{\omega}}_{0}/{\ensuremath{\gamma}}_{0}$ can exceed 2000, where ${\ensuremath{\omega}}_{0}$ and ${\ensuremath{\gamma}}_{0}$ are the mode angular frequency and damping rate. This value is much larger than any previously reported for other eigenmodes of a condensate. We also present the temperature variation of ${\ensuremath{\omega}}_{0}$ and ${\ensuremath{\gamma}}_{0}$.

DOI: 10.1103/physrevlett.88.250402

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arXiv:cond-mat/0111455 · Physical Review Letters

Transverse Breathing Mode of an Elongated Bose-Einstein Condensate

Frédéric Chevy, Vincent Bretin, P. Rosenbusch, Kirk W. Madison, Jean Dalibard

Published Jun 6, 2002• 173 citations

arXiv HTML PDF

Abstract

We study experimentally the transverse monopole mode of an elongated rubidium condensate. Because of the scaling invariance of the nonlinear Schr"odinger (Gross-Pitaevskii) equation, the oscillation is monochromatic and sinusoidal at short times, even under strong excitation. For ultralow temperatures, the quality factor

Q\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}{\ensuremath{\omega}}_{0}/{\ensuremath{\gamma}}_{0}

can exceed 2000, where

{\ensuremath{\omega}}_{0}

and

{\ensuremath{\gamma}}_{0}

are the mode angular frequency and damping rate. This value is much larger than any previously reported for other eigenmodes of a condensate. We also present the temperature variation of

{\ensuremath{\omega}}_{0}

and

{\ensuremath{\gamma}}_{0}

DOI: 10.1103/physrevlett.88.250402

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Q\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}{\ensuremath{\omega}}_{0}/{\ensuremath{\gamma}}_{0}

can exceed 2000, where

{\ensuremath{\omega}}_{0}

and

{\ensuremath{\gamma}}_{0}

are the mode angular frequency and damping rate. This value is much larger than any previously reported for other eigenmodes of a condensate. We also present the temperature variation of

{\ensuremath{\omega}}_{0}

and

{\ensuremath{\gamma}}_{0}

m=2

mode or for more isotropic trap potentials, suggesting further possible experimental tests of our theory.